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Previous session missing after upgrade; after restoring from backup, Firefox hangs immediately upon startup.

Mac OS X, Firefox v59.

Today I upgraded Firefox to 59. When restarting after the upgrade, I lost my session, and "Restore Previous Session" was greyed out. This is the second time this has happened to me -- it happened when Firefox first forced me onto Quantum, and it took me quite a long time to track down what to do to recover my session -- so it was a real bummer that this happened yet again after an upgrade. Anyway, I did what worked the last time, and what googling this time around seemed to confirm was the thing to do: after closing Firefox, look in sessionstore-backups, find the jsonlz4 file that seemed appropriate, and copy it into sessionstore.jsonlz4 in the profile directory. Then, I restarted Firefox.

Upon restarting, Firefox hangs almost immediately. It creates the windows I had open, creates the tabs I had open in each window; but before loading the content of the visible tab, it locks up. The spinning wheel goes forever; CPU % goes to 100; the memory allocation goes up and up until the system runs out of memory; and nothing in the windows or in the context menu is responsive. The only thing one can do is kill Firefox from the command line (or, I guess, reboot). It cannot be closed from within Firefox, as the menus are not responsive.

After that kill, Firefox will restart normally, but my old session is again lost and "Restore Previous Session" is once again greyed out. Attempting to recover my old session again causes it to hang immediately upon restart. Wash, rinse, repeat.

Why is Firefox Quantum so unstable with respect to retaining/recovering the previous session? How can I recover my previous session?

Thanks much.

Mac OS X, Firefox v59. Today I upgraded Firefox to 59. When restarting after the upgrade, I lost my session, and "Restore Previous Session" was greyed out. This is the second time this has happened to me -- it happened when Firefox first forced me onto Quantum, and it took me quite a long time to track down what to do to recover my session -- so it was a real bummer that this happened yet again after an upgrade. Anyway, I did what worked the last time, and what googling this time around seemed to confirm was the thing to do: after closing Firefox, look in sessionstore-backups, find the jsonlz4 file that seemed appropriate, and copy it into sessionstore.jsonlz4 in the profile directory. Then, I restarted Firefox. Upon restarting, Firefox hangs almost immediately. It creates the windows I had open, creates the tabs I had open in each window; but before loading the content of the visible tab, it locks up. The spinning wheel goes forever; CPU % goes to 100; the memory allocation goes up and up until the system runs out of memory; and nothing in the windows or in the context menu is responsive. The only thing one can do is kill Firefox from the command line (or, I guess, reboot). It cannot be closed from within Firefox, as the menus are not responsive. After that kill, Firefox will restart normally, but my old session is again lost and "Restore Previous Session" is once again greyed out. Attempting to recover my old session again causes it to hang immediately upon restart. Wash, rinse, repeat. Why is Firefox Quantum so unstable with respect to retaining/recovering the previous session? How can I recover my previous session? Thanks much.

All Replies (3)

Hi cmetzler, I do not know the precise answer to this question, but my guess is that Firefox is not happy reloading one of the active tabs:

Why is Firefox Quantum so unstable with respect to retaining/recovering the previous session? How can I recover my previous session?

Could I suggest you extract your session history file to an HTML page of clickable links and use that to reload the tabs you need right away; you can keep the others for reference. See: https://www.jeffersonscher.com/res/scrounger.html

Since we don't know which tab is causing the problem, it's difficult to advise on more specific edits to the file (i.e., to bypass the problem).

jscher2000 said

Hi cmetzler, I do not know the precise answer to this question, but my guess is that Firefox is not happy reloading one of the active tabs: Could I suggest you extract your session history file to an HTML page of clickable links and use that to reload the tabs you need right away; you can keep the others for reference. See: https://www.jeffersonscher.com/res/scrounger.html Since we don't know which tab is causing the problem, it's difficult to advise on more specific edits to the file (i.e., to bypass the problem).

Hi. Thanks for your quick response.

Some further information: I went to a backup of my entire profile that dates from before the upgrade, and still got the hang immediately upon startup. So somehow Firefox v59 seems to be unhappy with recent sessions of mine in a way that Firefox v57 (which I upgraded from) was not, as I was able to start v57 numerous times with the same profile that I now cannot use to start v59.

Re: the scrounger page, I'm not sure what to put in there: the sessionstore file, or the storage.js file I see in browser-extension-data/Tab-Session-Manager@sienori ?

cmetzler said

I went to a backup of my entire profile that dates from before the upgrade, and still got the hang immediately upon startup. So somehow Firefox v59 seems to be unhappy with recent sessions of mine in a way that Firefox v57 (which I upgraded from) was not, as I was able to start v57 numerous times with the same profile that I now cannot use to start v59.

What if you do NOT use Firefox's recovery.jsonlz4 at startup, but instead use a Tab Session Manager file. Does that have the same problem?

Re: the scrounger page, I'm not sure what to put in there: the sessionstore file, or the storage.js file I see in browser-extension-data/Tab-Session-Manager@sienori ?

Whatever file you want to scrounge from is the file to drop on there, but only one at a time.